In the scenes set in 1995, the computer monitors are modern LCD screens inside CRT enclosures.
When the reporter is called to investigate the disappearance of O'Hair in 1995, his phone clearly says "Lucent". Lucent did not exist until September of 1996.
In one scene Madalyn tells her parents in the 1950s that a man who left her "kicked her to the curb". That expression was not used until the 1990s.
At approximately the 33 minute point in the film, when O'Hair and two others are being held in a hotel room as part of a kidnapping plot, the radio plays a news item describing the collision of a Chinese fighter aircraft with a US "spy" plane. The kidnapping took place in August of 1995, but the spy plane news story was about the "Hainan Incident" of April, 2001, in which a Chinese fighter aircraft collided with a US Navy EP-3 aircraft. The American aircraft landed on Hainan Island and the crew were detained for ten days.